SCTP is a reliable universal transmission layer protocol used on an Internet Protocol (IP) network. The protocol is initially designed for sending telecommunication signaling, has such characteristics as supporting multi-homing, multi-streaming, initialization protection, message framing, configurable unordered sending, and smooth shutdown, and the protocol has very high reliability and security. Therefore, many mainstream operating systems (such as Linux, BSD, and Solaris) begin to support the SCTP, so that currently services transmitted by using the protocol on a network are gradually increased.
In the prior art, a quintuple (a source IP, a destination IP, a source Port, a destination Port, and a transmission layer protocol) is used to identify one Transmission Control Protocol (TCP)/User Datagram Protocol (UDP) packet. Information saved in a data stream is associated with the quintuple, and a subsequent packet of the data stream uses the quintuple to index the information saved in the data stream.
However, because of a characteristic that the SCTP supports the multi-homing, i.e. the same association of the SCTP may use several different quintuples for interaction. Because a plurality of quintuples exists in the association, if the quintuple that is used for identifying the TCP/UDP packet is used to identify an SCTP association, only one or few quintuples involved in the association can be identified, a packet using other quintuples involved in the association for communication is not identified, thereby causing a large quantity of missed identification.